What US government agency regulates banking IRA practices?

I would like to make a formal complaint about the handling of my IRA by a major US bank. The bank's improper practices are costing me a penalty. I need to know the government agency that I should get in touch with, and any website or phone number would be of great help. Thanks to all!

I would check with the Federal Deposit Insurance Corporation(FDIC .

www.fdic.gov

But first check with your State Comptroller and le their office know what is going on too.

Can you be a bit more specific on the "improper practices"?